1. There cannot be ensured.
Even if case of centralized system and document ID checking, any can use ID of other person.
I disagree fully here. Plenty of online platforms have systems in place to prevent this, such as Eros and P411. Do your research on requirements.
2. No screening.
Only a considered reputation system.
This is exactly the same as a review board, a culture many sex workers are trying to get away from. Sex workers deserve the right to know if clients are safe, clean, and honour the agreed-upon donation. A simple points or reputation system does none of this.
3. Yes, that is exactly our survey showed.
That cash is the main reason of violence among sex workers? That's an absurd statement and your survey does nothing to back up any such claim because you haven't validated your survey with any research methods. You're just using it to promote the idea that tokens should be used instead of cash, but this in reality is a huge hassle and is likely going to drive people awat from your platform.
4. Yes, noone can provide guaranties. Even if case of centralized system and document ID checking.
I'm a sex worker and I would never use a site that has zero guarantees. Worldwide, there are already hundreds of websites that have a zero-guarantee policy: BackPage, Hidden Pages, City of Love, Lady Xena, Top Escort Babes, Euro Girls, 9 Escorts.. the list goes on. My time and efforts are better spent elsewhere.